Why didn't any of the group find it odd that the skyline was going dark all at once? Star light takes years to reach other star systems, and the time it takes to reach another planet is directly proportional to its distance. That brings to mind two possibilities:
a) The stars were destroyed long ago in the past using a level of coordination that boggles imagination. It's also a type of coordination that would have little purpose (unless Aya knew where Hal and his group would be and wanted to send a message). It also brings up a whole host of other questions (such as why nobody was aware of the problem years ago).
b) Something is wiping out all light in the universe almost instantaneously. Is more than light being wiped out instantaneously? Can they safely enter the dark region? Will they have to fight while literally being blind (as light is necessary for sight)?